So I have some questions regarding behavior. I have 5 fish from two different sources and all seem to be doing ok. The largest of the group(fish A) has taken up the right side of the tank (about 1/3rd, the caves) and another smaller but very aggressive fish has taken over the opposite 1/3rd of the tank (the shell-bed, fish B) in the middle is a rock island with lots of cave and nooks and crannies where the other 3 fish live one of these 3 smaller fish (fish C) seems to have taken up around a cave place int he back of the tank and seems to be showing some interest in the other fish but also chases others out of his territory. ok so my question is which fish stake out and defend territory the males or females? or is it the stronger more dominant fish regardless of size? right now one of my smaller fish is holding down a considerable portion of my tank and even the larger fish won't go into the area but this fish will roam the entire tank but return to defend the territory. the tank is a 36" 40 gal breeder and no one is getting targeted specifically. Could I have all males or females, or are the still too young to know? The largest fish is about definately bigger and shows the aggressive barring that the other fish don't. The tank has been up for about a month and the water parameters are within the appropriate range for these fish. I've doubled the shells, but the territories haven't changed. Any answers would be appreciated
The most common scenario, especially in a small tank like a 36" is that 2 of the fish will form a pair and reject the others.
I would expect the male to be most aggressive but no guarantees. The barring can be dominance or submissiveness, so maybe the small aggressive one is male and the large barred one is male being rejected from the tank.